Marty Schulman with Alabama Water Watch holds up a tank containing a watercress darter.

A 2008 fish kill of thousands of endangered fish at Roebuck Springs Park could cost the city of Birmingham about $4 million.

The U.S. Fish and Wildlife Service Federal officials announced today they are seeking nearly $3 million in penalties for the fish kill.

In addition, the Alabama Department of Conservation and Natural Resources has also fined the city $1 million for the death of the darters and the deaths of more than 2 million protected snails.

The federally endangered 2-inch fish were almost wiped out when city employees removed a dam at a Roebuck Springs pool filled with the rare fish at the park. About 12,000 darters were killed as the water rushed out of the pond, leaving the fish stranded in the mud.

Daniel Drennen, a Fish and Wildlife biologist and recovery biologist for the darter, estimated about half of the original population remain.

Federal officials called the 2008 accident one of the largest fish kills in the history of the Endangered Species Act. Federal officials said the city had taken responsibility for damaging the dam and began repair efforts. However, they maintain the city failed the take all the steps needed to protect the fish and its habitat.

"Back in 2008 we sent a demand letter with 18 requests. They pretty much accomplished five out of that," said Denise Rowell, a U.S. Fish and Wildlife Service spokeswoman at the Alabama field office. "The city of Birmingham is blessed to have these rare fish in their own backyard and we want them to work with us to protect that."

The city has 45 days to respond.

"They can definitely negotiate with us," Rowell said. "Our ultimate goals is not to get a lot of money from Birmingham. We just want to do what's best for the fish."